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Date: Wed, 10 Sep 2008 16:58:32 +0100
From: Jamie Lokier <jamie@shareable.org>
Subject: Re: [Qemu-devel] [PATCH 2/10] Allow the monitor to be suspended
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To: qemu-devel@nongnu.org
Cc: Chris Wright <chrisw@redhat.com>, Uri Lublin <uri.lublin@qumranet.com>, Anthony Liguori <aliguori@us.ibm.com>, kvm@vger.kernel.org

Avi Kivity wrote:
> (logically we would copy all of the data of all block devices, but 
> that's not very practical, so we assume shared storage).

Speaking of that, if the guest RAM were a memory-mapped file, couldn't
that use shared storage too?

You'd have to be careful: it would need a distributed filesystem with
coherent mappings (i.e. not NFS), but they do exist.

I'm guessing that the bulk of time spent in migration/checkpointing is
saving the RAM image.  Using a memory-mapped file on shared storage
for RAM might make that faster.  (Or slower!).

-- Jamie